Use of Naftifine Hydrochloride 2% Cream and 39% Urea Cream in the Treatment of Tinea Pedis Complicated by Hyperkeratosis

February 2014 | Volume 13 | Issue 2 | Original Article | 162 | Copyright © February 2014

Leon Kircik MDa,b,c and Neh Onumah MDd

aDepartment of Dermatology, Indiana University School of Medicine, Indianapolis, IN
bPhysicians Skin Care, PLLC, Louisville, KY
cDepartment of Dermatology, Mount Sinai School of Medicine, New York, NY
dSkin of All Color LLC, East Windsor, NJ

The treatment of tinea pedis with hyperkeratosis has always been challenging due to presence of thick scales even after the resolution of active fungal infection. Patients usually identify hyperkeratosis with active disease. Therefore, a regimen of an antifungal and a keratolytic agent would be useful not only clearing the skin clinically but also addressing patients’ perceptions.

J Drugs Dermatol. 2014;13(2):162-165.


Tinea pedis is the most commonly encountered superficial cutaneous fungal infection in humans. In the United States, the highly contagious Trichophyton rubrum and Trichophyton mentagrophytes Var interdigitale are recognized as the primary causative organisms, T. rubrum accounting for more cases. Epidermophyton floccosum infects the plantar skin less frequently. Approximately 10 to 20% of the general population has been affected by tinea pedis. About 70% of these infections are in adults.1 The natural course of dermatophyte infection eventuates in epidermal thickening, hyperkeratosis, and scale production. As with many skin diseases, tinea pedis can impact the patients’ quality of life with symptoms of pruritus, burning, stinging, discomfort and or pain. Choosing the appropriate antifungal treatment, systemic or topical, may result in clinical resolution. However, the disease recurrence rate is high, up to 70% depending on the source. The reinfection rate is often related to persisting risk factors, inadequate clearance of the primary infection and in some cases due to patient noncompliance with the prescribed therapy.2
Notwithstanding, even with complete eradication of the dermatophyte, patients often contend that their infection persists due to the obvious presence of hyperkeratosis. Explaining to patients that their infection has resolved and that hyperkeratosis is the skin’s response to the dermatophyte is usually not well understood and received, even with evidence of a negative fungal skin culture and mycological cure.
Consequently, the significance of choosing a treatment regimen that addresses both clearance of active infection and reversal of hyperkeratosis cannot be underscored and should be strongly considered when treating this patient population. Furthermore, it is expected that the addition of a keratolytic agent to resolve the excess horny layer will assist the prescribed topical antifungal therapy possibly with better penetration, although this has not been formally measured. With that in mind, we examined the use of naftifine hydrochloride cream 2% and 39% urea cream in the treatment of hyperkeratotic tinea pedis.


We conducted a single center, open-label pilot study. Prior to initiation of this study, the protocol and informed consent were reviewed and approved by a central IRB. The purpose of this study was to examine the use of naftifine hydrochloride 2% cream and 39% urea cream in the treatment of hyperkeratotic tinea pedis. Eleven male and female subjects 18 years of age and older clinically diagnosed with mild to moderate hyperkeratotic tinea pedis on the Investigator Global Assessment (IGA) scale were enrolled in the study. The IGA scoring system used to rate current severity of hyperkeratosis was based on clinical appearance of the disease at the time of assessment and was graded as follows: 0=clear, 1=almost clear, 2=mild disease, 3=moderate disease, 4=severe disease, and 5=very severe disease. To participate in the study, all subjects had to understand and sign the informed consent and HIPAA authorization forms and agree to follow study procedures. Subjects were screened at the baseline visit and excluded from the study if they reported participation in an investigational drug trial within 30 days of their visit, had used any oral antifungal or steroid medication within 1 month or any topical antifungal, keratolytic, or steroid treatment within 2 weeks of their baseline visit, had a medical condition that in the investigator’s judgment precluded study participation, had a history of non-compliance or unreliability, or a known history of alcohol or drug abuse within the past 5 years. All female subjects